$re = '/\b[a-zA-Z]*\d{5,}[a-zA-Z]*\b/m';
$str = 'Corresponding to\\n"
... "1 102742238 CN A 2012-10-17 ZTE USA Inc. US20130094411A1\\n"
... "3 20150318972 2015-11-05 Zhang et al.\\n"
... "2 20130128860 2013-05-23 Zhang\\n"
... "1 20130094411 2013-04-18 Zhang\\n"
... "EFS Web 2.1.17\\n"
... "Examiner Signature Date Considered\\n"
... "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal\\n"
... "1 Terrestrial Radio Access (E-UTRA); Physical channels and modulation (Release 12), 3GPP TS 36.211 V12.7.0\\n"
... "fONAR_ NAN 12R nanac\\n"
... "vs Corresponding to\\n"
... "4 2014110837 WO Al 2014-07-24 Fujitsu Ltd. et al. US20150318972A1\\n"
... "3 2014107012 WO Al 2014-07-10 LG Electronics Inc.\\n"
... "; Corresponding to\\n"
... "2 103120006 CN A 2013-05-22 ZTE Corporation US20130128860A1\\n"
... "EFS Web 2.1.17\\n"
... "| |\\n"
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php